Mill



April 1, 11930.

A. STEINBRUCZKNER MILL I Filed Nov. 30, 1927 3 Sheets-Sheet l fnventur:

April 1, 193.0.

A. STEINBRUCKNER 1,752,860

MILL Filed so, 1927 s Sheets-Shet 2 Mi rant April 1, 1930.

ASTEINBRUCKNER ,860 7 MILL Filed Nov. so, 1927 5 Sheets-Sheet 3 Ratented Apr. 1, 1930 UNITED STATES ADOLF STEINBRU'GKNER, OF DUISB'IIRG, GERMANY MILL Application filed November 30, 1927, Serial No. 236,749, and in Germany December 8, 1926.

The invention relates to a mill intended to grind minerals, earths, cereals and the like and having a grinding work which is limited circularly and may be a crushing or striking 6 work. i

The invention hasjreference to the manner of sifting the grits from the flour. Accord ing to the inventionfthis sifting operation takes place at least for the greater part with- 10 in the mill, and in particular by means of an air current which is led circularly around the circular chamber of the grinding work. In order to be able to adapt the quantity of supplied air to the need that varies according to the nature of the material to be ground, within the Widest limits and exactly, that means in a manner causing a fine sifting, a branch is provided on the air conduit before its junction with the mill, through which branch a portionof the air current generated by a blower is prevented from entering the mill and is led to any other place of utilization or may be united again with the air current leaving the mill. To this end a device is provided serving for the regulation of the air current which eventually may be a long distance regulation for the current that is branched off before the mill.

In the circular chamber surrounding the grinding Work a mechanical conveyer is further arranged for the material producedin the mill, which conveyer rotates in this chamber and co-operate's wit the above-mentioned pneumatic conveying or sifting device, this co-operation of the two conveyers within the mill taking place in such a manner, that the mechanical conveyer always supplies anew to the mill work the grits leaving the latter, whilst the pneumatic conveyer the air current of which does not enter the mill work but flows only around it and does thus not interfere with the grinding operation takingplace therein, leads oif the flour immediately. A further sifting may take place within a sifter attached to the mill, which Sifter supplies again to the mill the material not yet ground finely enough. Under certain circumstances, however, the two mentioned conveying and sifting means arranged in combination with the mill itself will do satisfying work.

In order to allow of my invention to be more easily understood, some preferred em bodiments of a mill constructed accordinges to my invention are illustrated by way of example in the drawings which accompany and form part of this specification. In these drawings Figure 1 is a vertical section on the line G-D of Figure 2, Figure 2 is a vertical section on line AB of Figure 1, Figure 3 is a fragmentary view of another embodiment, whilst Figure 4 is a vertical section through a third embodiment.

Referring now to these figures, (1 denotes the mill casing in which the mill work is arranged that is limited by a cylindrical body or ring 1". The work shown in Figures 1 and 2 consists of three rollers 0 around which the ring r rotates, whilst in the embodiment 7 0 shown in Figure 4 the work operates by strik' ers b which rotate Whilst the ring 1" is stationary here. The material to be ground is ap plied to the mill work from a feeding means 9 ofeany design through a assage h.

Between the casing a an the ring 1' or 1', Figure 4, an annular space 6 is left, in which amechanical conveyer rotates, consisting e. g. in a bucket conveyer d. I

' In the embodiment illustrated in Figures 1, 2 and 4 this conveyer d rotates independently of the mill work, whereby the advantage is afforded, of the rate of revolutions of the mill work and that of the conveyer being enabled to better be adapted to the special requirements thereof andindependently of one another. In the embodiment illustrated in Figure 3 the conveyer, viz,rthe buckets (1 are arranged; on the ring '1" itself at a certain,

distance away from its circumference. This construction ofi'ersthe advantage of a special drive for the conveyer being dispensed with. On or nearly on the summit of the conveyer (1 channels f lead from the annular space 6 into the interior of the mill, so that the material that raises in the buckets d or d within the annular space 6 and emptied on the top thereof returns to the mill work through these channels f. Near its bottom the annular space 6 is equipped with a tangentially piece m opens into the annular space 8 the ing manner:

arranged mouth piece on to which a blowernis attached. On the place where the mouth Wall ofthe .casing a-has a horizontal guide grate 23. Before the mouth piece m a'conduit 0 branches ofl' in upward direction. In the embodiments shown in Figures-:1, 2 and 4 this conduit 0 is united'with a conduit j that around the mill work and not even partly through .the latter. The air current does not, further, interfere both with the return of the grits at the point f where the grits are supplied anew, and with the supply of the fresh opens on the top of the annular spaces at i, see Figure 1. .A nixer'k fitted with inner helically arranged bafile plates int-is arranged on the junction of the conduits 0 and j, the

latter uniting at an acute angle A damper p is arranged inthe-mouth piece in WhlCh damper serves to more or less throttle the passage m leading from the blower to the annular space 6. The damper 3) may be connected to an electric or mechamc long distance controlling apparatus denoted by p The described mill operates in the follow-- The material to be ground and fed from v the feeding device 9 to the mill work falls,

as .far as it has been disintegrated correspondingly, on the bottom down into the an nular space ethrough the gap a left between ring 1' or i f and casing a, see Figure 2. In the space e the grits are'taken up by the conveyer d or d and supplied anew to-the -mill work, .whilst the flour is taken with in several layers by the air blown-in in several jets'through theguide grate t tangentiall to ring and is led off from the m ll'throu fore its junction with said conveyer to b the outlet 1' and conduit 7'. The power of t e,

air currentcan be so regulated, that the pneuf' matic conveyer takes off only the fine flour, whilst the mechanical conveyer supplles over andover again the grits, until even the latter have been so finely ground, that they are also taken with by the air conveyer. In this manner a perfect sifting may be established within the mill itself, so that no sifting ma.- chine-needsto be arranged behipd the mill. Of course, a sifting-device s can nevertheless 'be inserted in the conduit j, by means of which device the coarse flour is again supplied to hemill at a. v w

The regulationof the power and quantity of the air is effected by adjusting the damper p, eventuall from a distant station by means of the longdis'tance controlling apparatus 12 The air that does notpass through the mill flows through conduit 0- and unites 1n the mixer h with the air leaving the mill through outlet 1'. In the mixer is the two air currents arecompletely mixed and, as the speed of the air current supplied through conduit 0 is superior to that of the air current supplied from outlet 21, the first-named air-current exerts an injector-like action upon the lastnamed. air current. Furthermore, as the air inlet 'm andithe air outlet are located close to one another, the. described :conveying'and sifting air currenttravels the longest'possible way within the mill and this merely portionof the air forced thro "ing the proportion of air; b

material, as both material currents are led into the mill work throughse arate channels, whilst the conveying-an sifting air current circulates outside around the mill .veyor arranged on the. outer surface of said 7 work and adapted to operate concentrically thereto and to lead off ground material from the mill, an air conduit leading to saidiconveyer, and an outlet in said air conduit be- P a proportion of theair forced throug the conduit to the conveyer. Y

2. A. mill comprising a mill work having. a cylindrical outer surface, .a pneumatic conveyer arranged'on the outer surface of said i work and adapted to operate concentrically theretoand to lead off ground material from the mill, an air conduit leading to said eonveyer, an outlet in said air'conduit beforeits junction with said conveyer tobypass a pro the conduit to the conveyer,fand means or regulatpassed through the-outlet with respect to t eproportion of air'forced through the conduit to'the conveyer.

3. A mill comprising a millwork having a cylindrical outer surfape, a pneumatic conveyer arran ed on the outer surfaceiof said work and adapted to' operate'condciitrically thereto and to lead off ground material from the mill, an air conduit lead' said conveyer, an outlet in said'air con nit before its junction with said conveyer to bypass a proportion of the air forced through the conduit to the conveyer, and long distance controlled work and a thereto and to lead oflt ground material from means for regulating the proportion of air bypassed through the outlet with res set to the pro ortion 0 air forced through t e conduit to t e conveyer.

4. A mill comprising a mill workohaving a cylindrical outer surface, a pneumatic con:

veyer arranged on the outer surface of said aptedto operate concentrically.

the'mill, an air. supplying conduit leading to and an air conduit leading away from, said conveyer, and an air bypassing conduit branched off from said air supplying eonduit before the junction of the latter with said conveyer and opening into said air conduit leading away from said conveyer. i 5'. A mill comprising a mill Work having a cylindrical outer surface, a pneumatic conveyer arranged on the outer surface of said work and adapted to operateconcentrically thereto and to lead ofi ground material from the mill, an air supplying conduit leading to and an air conduit leading away from, said conveyer, a conduit branched off from said air supplyin conduit before the junction of the latter with said conveyer and opening into said air conduit leading away from the latter, and an air mixer inserted on the junction of said branch and said last-named conduit.

6. A mill comprising a mill work having a cylindrical outer surface, a pneumatic conveyer arranged on the outer surface of said work and adapted to operate concentrically thereto and to lead off ground material from the mill, an air supplying conduit leading to and an air conduit leading away from, said conveyer, a conduit branched off from said air supplying conduit before the junction of the latter with said conveyer and opening into said conduit leading away from the latter,'and an air mixer inserted on the junction of said branch and said last-named conduit and having helical bafiie plates.

7. A mill comprising a mill work having a cylindrical outer surface, a pneumatic conveyerv arranged on the outer surface of said work and adapted to operate concentrically thereto and to lead off ground material from the mill, an air supplying conduit leading to and an air conduit leading away from, said conveyer, said two conduits opening close to one another into said conveyer'opposite to the direction of the supplied air current, and a conduit branched ofi from said air supplying conduit before the junction of the latter with said conveyer and opening into said air conduit leading away from said conveyer.

8. A mill comprising a mill work having a cylindrical outer surface, a pneumatic conveyer arranged on the outer surface of said work and adapted to operate concentrically thereto and to lead off ground material from the mill, an air supplying conduit leading to and an air conduit leading away from, said conveyer, and a conduit branched off from said air supplying conduit before the junction of the latter with said conveyer and opening into said air conduit leading away from said conveyer at an acute angle.

9. A mill comprising a mill work having a cylindrical outer surface, a pneumatic conveyer arranged on the outer surface of said work and adapted to operate concentrically theretoand to lead off ground material from,

the mill, an air supplying conduit leading to and an air conduit leading away from, said passin conveyer, a conduit branched off from said air supplying conduit before the junction of the latter with said conveyer and opening ina .cylindrical outer surface, a mechanical conveyerearranged on the circumference of said work and adapted to move concentrically thereto and to supply material to said mill work, a pneumatic conveyer arranged on the outer surface of said work and adapted to operate concentrically thereto and to lead ofl ground material from the mill, an air supplying conduit leading to and an air con duit leading away from, said conveyer, and a conduit branched off from said air supplying conduit before the junction of the latter with said conveyer-and opening into said air conduit leading away from said conveyer.

11. A mill comprising a mill work having a cylindrical outer surface, a mechanical conveyer arranged on the circumference of said work and adapted to move concentrically branched off from said air supplying con- I duit before the junction of the latter with said conveyer and opening into said air conduit leading away from the latter, and a sifting device inserted in the latter conduit. 12. In a mill, in combination, a material grinding medium, a mechanical conveyer for refeeding the material to the grinding medium and pneumatic means for conveying out of the mill the reground material which has previously been discharged from the grinding medium.

13. In a mill, in combination, a material grinding medium, a mechanical conveyer for refeeding the material to the grinding medium and pneumatic means for conveying out of the mill the reground material which has previously been discharged from the grinding medium, and means for preventing the air from the pneumatic means from into the grinding medium.

14. n a mill, in combination, a material grinding medium, and pneumatic means for conveying the ground material discharged from the grinding medium out of the mill, and means for causing the air from the pneumatic means to be circulated circumferentially around the exterior of the grinding me-- and means for causing the air from .the pneumatic means to be circulated circumferentially around the exterior of the grinding medium, said air being prevented from passing 5 into thegrinding medium.

16. In a mill, in combination, a material grinding medium, a surroundin mechanical ponveying means independent 0 the material grinding medium for conveying the material discharged from the grinding medium, and means 'for refeedingth'e material from the conveying means into the grinding medium.

17 In a mill, in combination, rotary grinding medium, rotary conveying means sur-- rounding the grinding medium and inde-- pendent thereof for conveying the material discharged from the grinding medium, inde; pendent drives for grinding medium and conveying'means, and'means for refeeding the 20 material from the conveying means into the grinding medium. Q

18. In a mill, in combination, a rotary grinding medium including an open sided ring member, a cylindrical casing surround '25 ing the ring member, the end walls of the casing spaced apart from the sides of the ring for permitting discharge of the ground material from the interior of the ring into A the bottom of the casing. 19. In a mill, in combination, a rotary grinding medium including an open sided ring member, a cylindrical casing'surround-v ing thering member, 'the end walls of the casin spaced apart from the sides of the ring %or permitting discharge of the ground material from the interior of the ring into the bottom of the casing, a rotary bucket conveyer surrounding the ring member for picking up the ground material discharged into 4.0 the bottom portion of the casing, and means for refeeding the material into the interior of the ring from the rotary conveyer.

20. In a mill, in combination, a cylindrical casing, a grinding medium disposed central- Sly of the casing, and means for forcing air under pressure into the casing substantially tangentially to. the peripheral wall thereof into a ring shaped uno structed space between the peripheral wall and the outer sur-' 0- face of the grinding ring whereby it 01 lows the curve of such space.

In testimony whereof I afiix my signature.

7 ADOLF STEINBRUCKNER. 

